Memoir, descriptive and explanatory, to accompany the new chart of the Atlantic Ocean : and comprising instructions, general and particular, for the navigation of that sea : also, 1: Tables of the determined positions of all its principal points, &c., with the biblio_authorities, illustrated by notes. 2: A copious explanation of the winds, tides, currents, &c.; and of the different passages over the Atlantic , as controlled by these phænomena, including a general tide-table. 3: Descriptions of the coasts and islands ; particularly of those parts of the African Coast hitherto imperfectly known, and of the Azores, Madeiras, Cape Verde, and Bermudas', islands . 4: A description of rocks, shoals, and vigias; with the biblio_authorities on which they have been inserted in the chart / compiled by John Purdy.